This is hard to describe, but the black enamel-like part below the protruding lip in the back of our Prius seem to have gotten chipped. Should we just use touch up paint to fix it? Should I put some enamel/sealant like thing to make sure it doesn't get worse? It would probably help if I know what that black part is called.
Try using a sharpie marker to touch it up. Seriously, you might be surprised. It won't be noticeable if you go over the edge into the paint. If you try it with enamel and go over the edge it will be noticeable. You've probably got one right there in that kitchen junk drawer we all have.